SU1159690A2 - Punch for piercing openings - Google Patents

Abstract

PUNCHER FOR PUNCHING OF OPENINGS, according to auth. No. 1031582, about the fact that, in order to improve the quality of the holes due to the exclusion of the possibility of burrs on it, two flat flats with a depth equal to 10-15% of the maximum overall dimension of the cross section of the punch are made at its working end, each of the bald faces it is formed by two mutually perpendicular planes, the first of which is parallel to the axis of the punch and corresponds to the plane of the other flat and perpendicular to the cutting face passing through the axis of the punch, and the second is parallel to the corresponding plane other flats, perpendicular to the axis of the punch and removed from the working end of the punch by an amount 15–30% larger than the maximum overall dimension of the cross section of the punch, removing the intersection line of the first one forming the flat (L planes with the inclined cutting furthest from the working end of the punch verge .1; about ed; about

Description

The invention relates to devices used for punching holes in pipes, vessels, and other hollow articles, can be used in mechanical engineering and other industries, and is an improvement to the invention by the author. No. 1031582,

The purpose of the invention is to improve the quality of the holes by eliminating the likelihood of burrs on it.

FIGS. 1-3 are depicted in three projections; a panson for matrix-free punching, in particular, a circular aperture.

The working end of the punch is formed by three cutting edges 1-3. Two faces 1 and 2 are flat and inclined in opposite directions with the verdins displaced one relative to the other by the value H ,. The third cutting face 3 passes through the punch axis,

The working end of the punch has two flats, each of which is surrounded by two mutually perpendicular planes 4 and 5, 6 and 7. The planes 4 and 6 are parallel to each other and to the axis of the punch and perpendicular to the cutting face 3. The depth of both balds is less than the thickness of the material punched billet and is equal to 10-15% of the maximum overall size of the cross section of the punch. Planes 5 and 7 are removed from the corresponding conoses. nyai coHOB by L | and lj. The value of Li | exceeds the value of H by 15-30% of the maximum

the overall size of the cross section of the punch, in the case of punching

round hole h 0,1-О, 15 d and LI - (0,15-0,3) d.

When punching holes with a punch at the first stage, a burr is formed at the point of the contour corresponding to the point where the vertices of the inclined and longitudinal edges meet. Performing the flats at the working end of the punch allows displacement of the point where the vertices of the inclined and longitudinal edges align from the outer contour to the axis of the punch. This in turn allows a section of material with formed burrs to be removed into waste, resulting in the formation of a burr on the contour of the punched hole punching without a matrix is excluded. .

In the case, if the depth is less than the specified limit, then the burr is not completely removed when the hole is drilled in the tubular billet. With an increase above a specified limit, a significant increase in the deflection of the wall of the billet is observed

If the values of LI and L ;, are less than the specified limit, then a burr formed at the first stage, falling on the cutting surface of the flathead may leave a impression on the workpiece. Increasing the values of L (and Lj above the specified limit. Leads to an unjustified increase in the total length of the punch.

Example 1. When beamless punching holes with a diameter of 11 mm in the wall of a tubular billet with a diameter of 34 mm and a wall thickness of 5 mm from steel 20 use a punch having two flats with dimensions h 1, 5 mm 1 l 10 mm, 3 mm and H 8 mm, in comparison with with the base object, it allows to exclude the formation of burrs with a height of 0.3-0.6 mMo

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FIG. 2

FIG. 3

Claims (1)

PUNCH FOR PUNCHING HOLES, by Auth. No. 1031582, due to the fact that, in order to improve the quality of the holes by eliminating the likelihood of burrs on it, two flats were made at its working end with a depth of 10-15% of the maximum overall size the cross section of the punch, each of the flats is formed by two mutually perpendicular planes, the first of which is parallel to the axis of the core and corresponds to the plane of the other dihedron and is perpendicular to the cutting edge, ^and extending Erez axis of the punch, and the second - parallel to the corresponding plane Dru flat flats, perpendicular to the axis of the punch and removed from the working end of the punch by an amount exceeding 15-30% of the value of the maximum overall dimension of the cross section of the punch, removing the line of intersection of the first of the flats of the flank with the most inclined cutting face from the punch end. 1159690 2